Selective herbicides based on substituted aminotrizinones and substituted benzoyl-cyclohexandionen

ABSTRACT

The invention relates to novel herbicidal, synergistic active compound combinations comprising firstly known substituted aminotriazinones and secondly known substituted benzoylcyclohexanediones and, if appropriate, additionally a compound which improves crop plant compatibility, and which can be used with particularly good results for the selective control of weeds in various crops of useful plants.

The invention relates to novel herbicidal, synergistic active compoundcombinations comprising firstly known substituted aminotriazinones andsecondly known substituted benzoylcyclohexanediones and, if appropriate,additionally a compound which improves crop plant compatibility, andwhich can be used with particularly good results for the selectivecontrol of weeds in various crops of useful plants

Certain substituted aminotriazinones, such as, for example, thecompounds4-amino-6-(1,1-dimethylethyl)-3-methylthio-1,2,4-triazin-5(4H)-one(metribuzin), 4-amino-3-methyl-6-phenyl-1,2,4-triazin-5(4H)-one(metamitron) and4-amino-6-(1,1-di-methylethyl)-3-ethylthio-1,2,4-triazin-5(4H)-one(ethiozin), are known as herbicidally active substances (cf. DE-1795784,DE-2138031, U.S. Pat. No. 4,036,632).

Certain substituted benzoylcyclohexanediones, such as, for example, thecompounds 2-(2-chloro-4-methylsulphonylbenzoyl)-1,3-cyclohexanedione(sulcotrione) and2-(4-methylsulphonyl-2-nitrobenzoyl)-1,3-cyclohexanedione (mesotrione),are likewise known as herbicidally active substances (cf. EP-0137963 andWO-96/13163).

Surprisingly, it has now been found that a number of known activecompounds from the group of the substituted aminotriazinones, when usedtogether with known herbicidally active compounds from the group of thesubstituted benzoylcyclohexanediones, exhibit synergistic effects withrespect to the action against weeds and can be used particularlyadvantageously as broad-spectrum combination preparations for theselective control of weeds in crops of useful plants, such as, forexample, in cotton, barley, potatoes, maize, oilseed rape, rice, rye,soya beans, sunflowers, wheat, sugar cane and sugar beet.

The invention provides selectively herbicidal compositions,characterized in that they comprise an effective amount of an activecompound combination comprising

-   -   (a) at least one substituted aminotriazinone of the general        formula (I)        in which    -   R¹ represents straight-chain or branched alkyl having 1 to 6        carbon atoms or represents phenyl and    -   R² represents in each case straight-chain or branched alkyl or        alkylthio having in each case 1 to 6 carbon atoms        -   (“compounds of group 1”) and    -   (b) at least one substituted benzoylcyclohexanedione of the        general formula (II)        in which    -   R³ represents nitro, cyano, halogen, or represents in each case        halogen-substituted, in each case straight-chain or branched        alkyl, alkoxy, alkylthio, alkylsulphinyl or alkylsulphonyl        having in each case 1 to 6 carbon atoms, and    -   R¹ represents nitro, cyano, halogen, represents in each case        optionally halogen-, C₁-C₄-alkoxy-, C₁-C₄-alkylthio-,        C₁-C₄-alkylsulphinyl- or C₁-C₄-alkyl-sulphonyl-substituted, in        each case straight-chain or branched alkyl, alkoxy, alkylthio,        alkylsulphinyl or alkylsulphonyl having in each case 1 to 6        carbon atoms, or represents alkylamino, dialkylamino,        dialkylaminocarbonyl or dialkylaminosulphonyl having in each        case 1 to 6 carbon atoms in the alkyl groups which are in        each-case straight-chain or branched        -   (“active compounds of group 2”)    -   and also, if appropriate, additionally    -   (c) a compound which improves crop plant compatibility, from the        following group of compounds:    -   4-dichloroacetyl-1-oxa-4-azaspiro[4.5]decane (AD-67),        1-dichloroacetylhexahydro-3,3,8a-trimethylpyrrolo[1,2-a]pyrimidin-6(2H)-one        (BAS-145138),        4-dichloroacetyl-3,4-dihydro-3-methyl-2H-1,4-benzoxazine        (benoxacor), 1-methylhexyl 5-chloro-quinoxalin-8-oxyacetate        (cloquintocet-mexyl), α-(cyanomethoximino)phenyl-acetonitrile        (cyometrinil), 2,4-dichlorophenoxyacetic acid (2,4-D),        2,2-dichloro-N-(2-oxo-2-(2-propenylamino)ethyl)-N-(2-propenyl)acetamide        (DKA-24), 2,2-dichloro-N,N-di-2-propenylacetamide (dichlornid),        N-(4-methylphenyl)-N′-(1-methyl-1-phenylethyl)urea (daimuron,        dymron), 4,6-dichloro-2-phenylpyrimidine (fenclorim), ethyl        1-(2,4-dichlorophenyl)-5-trichloromethyl-1H-1,2,4-triazole-3-carboxylate        (fenchlorazol-ethyl), phenylmethyl        2-chloro-4-trifluoromethylthiazole-5-carboxylate (flurazole),        4-chloro-N-(1,3-dioxolan-2-ylmethoxy)-α-trifluoroacetoxyphenoxime        (fluxofenim),        3-dichloroacetyl-5-(2-furanyl)-2,2-dimethyloxazolidine        (furilazole, MON-13900), ethyl        4,5-dihydro-5,5-diphenyl-3-isoxazolecarboxylate        (isoxadifen-ethyl), (4-chloro-2-methylphenoxy)acetic acid        (MCPA), (±)-2-(4-chloro-2-methylphenoxy)propanoic acid        (mecoprop), diethyl        1-(2,4-dichlorophenyl)-4,5-dihydro-5-methyl-1H-pyrazole-3,5-dicarboxylate        (mefenpyr-diethyl), 2-dichloromethyl-2-methyl-1,3-dioxolane        (MG-191), 1,8-naphthalic anhydride,        α-(1,3-dioxolan-2-ylmethoximino)phenylacetonitrile        (oxabetrinil),        2,2-dichloro-N-(1,3-dioxolan-2-ylmethyl)-N-(2-propenyl)acetamide        (PPG-1292), 3-dichloroacetyl-2,2,5-trimethyloxazolidine        (R-29148),        N-cyclopropyl-4-[[(2-methoxy-5-methylbenz-oyl)amino]sulphonyl]benzamide,        N-[[(4-methoxyacetylamino)phenyl]sulphonyl]-2-methoxybenzamide        and        N-[[(4-methylaminocarbonylamino)phenyl]sulphonyl]-2-methoxybenzamide        (the latter are in each case known from WO-A-99/66795)    -   (“active compounds of group 3”).

In general, 0.01 to 100 parts by weight of an active compound of group 2are present per part by weight of an active compound of group 1.

Preferred meanings of the groups listed above in connection with theformula (I) are defined below.

-   -   R¹ preferably represents straight-chain or branched alkyl having        1 to 5 carbon atoms or represents phenyl.    -   R² preferably represents in each case straight-chain or branched        alkyl or alkylthio having in each case 1 to 5 carbon atoms.    -   R¹ particularly preferably represents methyl, ethyl, n- or        i-propyl, n-, i-, s- or t-butyl, or represents phenyl.    -   R² particularly preferably represents methyl, ethyl, n- or        i-propyl, n-, i-, s- or t-butyl, methylthio, ethylthio, n- or        i-propylthio, n-, i-, s- or t-butylthio.    -   R¹ very particularly preferably represents n- or i-propyl, n-,        i-, s- or t-butyl, or represents phenyl.    -   R² very particularly preferably represents methyl, ethyl, n- or        i-propyl, methyl-thio, ethylthio, n- or i-propylthio.

Very particularly preferred mixing components of the general formula (I)which may be mentioned by way of example are:

-   -   4-amino-6-( 1,1-dimethylethyl)-3-methylthio-1        ,2,4-triazin-5(4H)-one (metribuzin),        4-amino-3-methyl-6-phenyl-1,2,4-triazin-5(4H)-one (metamitron)        and 4-amino-6-(1,1-dimethylethyl)-3-ethylthio-1,2,4-triazin-5        (4H)-one (ethiozin).

Very particular emphasis is given to the compound4-amino-6-(1,1-dimethylethyl)-3-methylthio-1,2,4-triazin-5(4H)-one(metribuzin).

Preferred meanings of the groups listed above in connection with theformula (II) are defined below.

-   -   R³ preferably represents nitro, cyano, halogen, or represents in        each case optionally halogen-substituted, in each case        straight-chain or branched alkyl, alkoxy, alkylthio,        alkylsulphinyl or alkylsulphonyl having in each case 1 to 5        carbon atoms.    -   R⁴ particularly preferably represents nitro, cyano, halogen,        represents in each case optionally halogen-, C₁-C₄-alkoxy-,        C₁-C₄-alkylthio-, C₁-C₄-alkyl-sulphinyl- or        C₁-C₄-alkylsulphonyl-substituted, in each case straight-chain or        branched alkyl, alkoxy, alkylthio, alkylsulphinyl or        alkylsulphonyl having in each case 1 to 5 carbon atoms, or        represents alkylamino, dialkylamino, dialkylaminocarbonyl or        dialkylaminosulphonyl having in each case 1 to 5 carbon atoms in        the alkyl groups, which are in each case straight-chain or        branched.    -   R³ particularly preferably represents nitro, cyano, fluorine,        chlorine, bromine, iodine, or represents in each case optionally        fluorine- and/or chlorine-substituted methyl, ethyl, n- or        i-propyl, n-, i-, s- or t-butyl, methoxy, ethoxy, n- or        i-propoxy, methylthio, ethylthio, n- or i-propylthio,        methylsulphinyl, ethylsulphinyl, n- or i-propylsulphinyl,        methylsulphonyl or ethylsulphonyl.    -   R⁴ particularly preferably represents nitro, cyano, fluorine,        chlorine, bromine, iodine, represents in each case optionally        fluorine-, chlorine-, methoxy-, ethoxy-, n- or i-propoxy-,        methylthio-, ethylthio-, n- or i-propylthio-, methyl-.        sulphinyl-, ethylsulphinyl-, n- or i-propylsulphinyl-,        methylsulphonyl- or ethylsulphonyl-substituted methyl-, ethyl-,        n- or i-propyl, n-, i-, s- or t-butyl, methoxy, ethoxy, n- or        i-propoxy, methylthio, ethylthio, n- or i-propylthio,        methylsulphinyl, ethylsulphinyl, n- or i-propylsulphinyl,        methylsulphonyl or ethylsulphonyl, or represents methylamino,        ethylamino, n- or i-propylamino, dimethylamino, diethylamino,        dipropylamino, dimethylaminocarbonyl, di-ethylaminocarbonyl,        dimethylaminosulphonyl or diethylaminosulphonyl.    -   R³ very particularly preferably represents nitro, cyano,        fluorine, chlorine, bromine, or represents in each case        optionally fluorine- and/or chlorine-substituted methyl, ethyl,        methoxy, ethoxy, methylthio, ethylthio, methyl-sulphinyl,        ethylsulphinyl, methylsulphonyl or ethylsulphonyl.    -   R⁴ very particularly preferably represents nitro, cyano,        fluorine, chlorine, bromine, or represents in each case        optionally fluorine-, chlorine-, methoxy-, ethoxy-, methylthio-,        ethylthio-, methylsulphinyl-, ethylsulphinyl-, methylsulphonyl-,        or ethylsulphonyl-substituted methyl, ethyl, methoxy, ethoxy,        methylthio, ethylthio, methylsulphinyl, ethylsulphinyl,        methylsulphonyl or ethylsulphonyl.

Very particularly preferred mixing components of the general formula(II) which may be mentioned by way of example are:

-   -   2-(2-chloro-4-methylsulphonylbenzoyl)-1,3-cyclohexanedione        (sulcotrione) and 2-(4-methylsulphonyl-2-nitrobenzoyl)-1        ,3-cyclohexanedione (mesotrione).

Very particular emphasis is given to the compound2-(2-chloro-4-methyl-sulphonylbenzoyl)-1,3-cyclohexanedione(sulcotrione).

The compositions according to the invention preferably contain oneactive compound of group 1 and one active compound of group 2 and, ifappropriate, additionally also one active compound of group 3.

Very particular preference is given to combinations of the activecompounds4-amino-6-(1,1-dimethylethyl)-3-methylthio-1,2,4-triazin-5(4H)-one(metribuzin) and2-(2-chloro-4-methylsulphonylbenzoyl)-1,3-cyclohexanedione(sulcotrione).

Surprisingly, it has now been found that the above-defined activecompound combinations of the substituted aminotriazinones of the formula(I) and the substituted benzoylcyclohexanediones of the formula (II)and, if appropriate, additionally a compound which improves crop-plantcompatibility exhibit a particularly high herbicidal activity combinedwith very good crop plant compatibility and can be used for theselective control of monocotyledonous and dicotyledonous weeds in avariety of crops, especially in cotton, barley, potatoes, maize, oilseedrape, rice, rye, soya beans, sunflowers, wheat, and sugar cane and sugarbeet, in particular in barley, maize, rice and wheat, very particularlyin maize.

Surprisingly, the herbicidal activity of the active compoundcombinations according to the invention of compounds of theabovementioned groups 1 and 2 exceeds the total of the actions of theindividual active compounds considerably.

Thus, not just a complementation of actions but a synergistic effect ispresent which could not have been predicted. The novel active compoundcombinations are well tolerated in a variety of crops, also effectinggood control of weeds which are otherwise difficult to control. Thus,the novel active compound combinations are a valuable addition to theherbicides.

The synergistic effect of the active compound combinations according tothe invention is particularly. strongly pronounced in certainconcentration ratios. However, the weight ratios of the active compoundsin the active compound combinations may be varied within relatively wideranges. In general, from 0.01 to 100 parts by weight, preferably from0.02 to 50 parts by weight and particularly preferably from 0.05 to 10parts by weight of active compound of group 2 are used per part byweight of active compound of the formula (I).

The following may be particularly emphasized as mixing components fromamongst the active compounds of group 3:

-   -   1-methyl-hexyl 5-chloroquinoline-8-oxyacetate        (cloquintocet-mexyl), ethyl        4,5-di-hydro-5,5-diphenyl-3-isoxazolecarboxylate        (isoxadifen-ethyl) and diethyl        1-(2,4-di-chlorophenyl)-4,5-dihydro-5-methyl-1H-pyrazole-3,5-dicarboxylate        (mefenpyr-diethyl) particularly suitable for improving tolerance        in barley and wheat and to a certain extent also in maize and        rice, and 4-dichloroacetyl-1-oxa-4-azaspiro[4.5]-decane (AD-67),        1-dichloroacetyl-hexahydro-3,3,8a-trimethylpyrrolo[1,2-a]-pyrimidin-6(2H)-one        (BAS-145138),        4-dichloroacetyl-3,4-dihydro-3-methyl-2H-1,4-benzoxazin        (benoxacor), 2,2-dichloro-N,N-di-2-propenylacetamide        (dichlormid),        3-dichloroacetyl-5-(2-furanyl)-2,2-dimethyloxazolidine        (flurilazole, MON-13900), and        3-dichloroacetyl-2,2,5-trimethyloxazolidine (R-29148)        particularly suitable for improving tolerance in maize.

All plants and plant parts can be treated in accordance with theinvention. Plants are to be understood as meaning in the present contextall plants and plant populations such as desired and undesired wildplants or crop plants (inclusive of naturally occurring crop plants).Crop plants can be plants which can be obtained by conventional plantbreeding and optimization methods or by biotechnological and recombinantmethods or by combinations of these methods, inclusive of the transgenicplants and inclusive of the plant varieties protectable or notprotectable by plant breeders' rights. Plant parts are to be understoodas meaning all aerial and subterranean plant parts and organs of theplants such as shoot, leaf, flower and root, examples which may bementioned being leaves, needles, stalks, trunks, flowers, fruitingbodies, fruits, and seeds, and also roots, tubers and rhizomes. Theplant parts also include vegetative and generative propagation material,for example cuttings, tubers, rhizomes, seedlings and seeds.

As already mentioned above, it is possible to treat all plants and theirparts according to the invention. In a preferred embodiment, wild plantspecies and plant cultivars, or those obtained by conventionalbiological breeding, such as crossing or protoplast fusion, and partsthereof, are treated. In a further preferred embodiment, transgenicplants and plant cultivars obtained by genetic engineering, ifappropriate in combination with conventional methods (GeneticallyModified Organisms), and parts thereof are treated. The term “parts” or“parts of plants” or “plant parts” has been explained above.

Particularly preferably, plants of the plant cultivars which are in eachcase commercially available or in use are treated according to theinvention. By plant cultivars are meant plants having new properties(“traits”), bred either by conventional breeding, by mutagenesis or byrecombinant DNA techniques. They may be cultivars, biotypes andgenotypes.

Depending on the plant species or plant cultivars, their location andgrowth conditions (soils, climate, vegetation period, diet), thetreatment according to the invention may also result in superadditive(“synergistic”) effects. Thus, for example, reduced application ratesand/or a widening of the activity spectrum and/or an increase in theactivity of the substances and compositions to be used according to theinvention, better plant growth, increased tolerance to high or lowtemperatures, increased tolerance to drought or to water or soil saltcontent, increased flowering performance, easier harvesting, acceleratedmaturation, higher harvest yields, better quality and/or a highernutritional value of the harvested products, better storage stabilityand/or processability of the harvested products are possible whichexceed the effects which are actually to be expected.

The preferred transgenic plants or plant cultivars (i.e. those obtainedby genetic engineering) which are to be treated according to theinvention include all plants which, in the genetic modification,received genetic material which imparted particularly advantageoususeful properties (“traits”) to these plants. Examples of suchproperties are better plant growth, increased tolerance to high or lowtemperatures, increased tolerance to drought or to water or soil saltcontent, increased flowering performance, easier harvesting, acceleratedmaturation, higher harvest yields, better quality and/or a highernutritional value of the harvested products, better storage stabilityand/or processability of the harvested products. Further andparticularly emphasized examples of such properties are a better defenceof the plants against animal and microbial pests, such as againstinsects, mites, phytopathogenic fungi, bacteria and/or viruses, and alsoincreased tolerance of the plants to certain herbicidally activecompounds. Examples of transgenic plants which may be mentioned are theimportant crop plants, such as cereals (wheat, rice), maize, soya beans,potatoes, cotton, oilseed rape and also fruit plants (with the fruitsapples, pears,. citrus fruits and grapevines), and particular emphasisis given to maize, soya beans, potatoes, cotton and oilseed rape. Traitsthat are emphasized are in particular increased defence of the plantsagainst insects by toxins formed in the plants, in particular thoseformed by the genetic material from Bacillus thuringiensis (for exampleby the genes CryIA(a), CryIA(b), CryIA(c), CryIIA, CryIllA, CryIIIB2,Cry9c, Cry2Ab, Cry3Bb and CryIF and also combinations thereof)(hereinbelow referred to as “Bt plants”). Traits that are alsoparticularly emphasized are the increased defence of plants againstfungi, bacteria and viruses by Systematic Acquired Resistance (SAR),systemine, phytoalexins, elicitors and resistance genes andcorrespondingly expressed proteins and toxins. Traits that arefurthermore particularly emphasized are the increased tolerance of theplants to certain herbicidally active compounds, for exampleimidazolinones, sulphonylureas, glyphosate or phosphinotricin (forexample the “PAT” gene). The genes which impart the desired traits inquestion can also be present in combination with one another in thetransgenic plants. Examples of “Bt plants” which may be mentioned aremaize varieties, cotton varieties, soya bean varieties and potatovarieties which are sold under the trade names YIELD GARD® (for examplemaize, cotton, soya beans), KnockOut® (for example maize), StarLink®(for example maize), Bollgard® (cotton), Nucotn® (cotton) and NewLeaf®(potato). Examples of herbicide-tolerant plants which may be mentionedare maize varieties, cotton varieties and soya bean varieties which aresold under the trade names Roundup Ready® (tolerance to glyphosate, forexample maize, cotton, soya bean), Liberty Link® (tolerance tophosphinotricin, for example oilseed rape), IMI® (tolerance toimidazolinones) and STS® (tolerance to sulphonylureas, for examplemaize). Herbicide-resistant plants (plants bred in a conventional mannerfor herbicide tolerance) which may be mentioned include the varietiessold under the name Clearfield® (for example maize). Of course, thesestatements also apply to plant cultivars having these or still to bedeveloped genetic traits, which plants will be developed and/or marketedin the future.

The plants listed can be treated according to the invention in aparticularly advantageous manner with the compounds of the generalformula I or the active compound mixtures according to the invention.The preferred ranges stated above for the active compounds or mixturesalso apply to the treatment of these plants. Particular emphasis isgiven to the treatment of plants with the compounds or the mixturesspecifically mentioned in the present text.

The treatment according to the invention of the plants and plant partswith the active compounds is carried out directly or by allowing thecompounds to act on their surroundings, environment or storage space bythe customary treatment methods, for example by immersion, spraying,evaporation, fogging, scattering, painting on and, in the case ofpropagation material, in particular in the case of seeds, also byapplying one or more coats.

Amongst the plants obtained by biotechnological and recombinant methods,or by combining these methods, plants which are emphasized are thosewhich tolerate so-called ALS, 4-HPPD, EPSP and/or PPO inhibitors, suchas, for example, Acuron plants.

The active compounds according to the invention can. be used, forexample, in the following plants:

-   -   Dicotyledonous weeds of the genera: Abutilon, Amaranthus,        Ambrosia, Anoda, Anthemis, Aphanes, Atriplex, Bellis, Bidens,        Capsella, Carduus, Cassia, Centaurea, Chenopodium, Cirsium,        Convolvulus, Datura, Desmodium, Emex, Erysimum, Euphorbia,        Galeopsis, Galinsoga, Galium, Hibiscus, Ipomoea, Kochia, Lamium,        Lepidium, Lindemia, Matricaria, Mentha, Mercurialis, Mullugo,        Myosotis, Papaver, Pharbitis, Plantago, Polygonum, Portulaca,        Ranunculus, Raphanus, Rorippa, Rotala, Rumex, Salsola, Senecio,        Sesbania, Sida, Sinapis, Solanum, Sonchus, Sphenoclea,        Stellaria, Taraxacum, Thlaspi, Trifolium, Urtica, Veronica,        Viola, Xanthium.    -   Dicotyledonous crops of the genera: Arachis, Beta, Brassica,        Cucumis, Cucurbita, Helianthus, Daucus, Glycine, Gossypium,        Ipomoea, Lactuca, Linum, Lycopersicon, Nicotiana, Phaseolus,        Pisum, Solanum, Vicia.    -   Monocotyledonous weeds of the genera: Aegilops, Agropyron,        Agrostis, Alopecurus, Apera, Avena, Brachiaria, Bromus,        Cenchrus, Commelina, Cynodon, Cyperus, Dactyloctenium,        Digitaria, Echinochloa, Eleocharis, Eleusine, Eragrostis,        Eriochloa, Festuca, Fimbristylis, Heteranthera, Imperata,        Ischaemum, Leptochloa, Lolium, Monochoria, Panicum, Paspalum,        Phalaris, Phleum, Poa, Rottboellia, Sagittaria, Scirpus,        Setaria, Sorghum.    -   Monocotyledonous crops of the genera: Allium, Ananas, Asparagus,        Avena, Hordeum, Oryza, Panicum, Saccharum, Secale, Sorghum,        Triticale, Triticum, Zea.

However, the use of the active compound combinations according to theinvention is in no way restricted to these genera, but also extends inthe same manner to other plants.

The active compound combinations to be used in accordance with theinvention can be employed not only in conventional cultivation methods(suitably spaced row crops), in plantation crops (for examplegrapevines, fruit, citrus) and in industrial plants and railtracks, onpaths and squares, but also for stubble treatment and in the minimumtillage method. They are furthermore suitable as desiccants (haulmkilling in, for example, potatoes) or as defoliants (for example incotton). They are furthermore suitable for use on non-crop areas. Otherfields of application are nurseries, forests, grassland and theproduction of ornamentals.

The active compound combinations can be converted into the customaryformulations such as solutions, emulsions, wettable powders,suspensions, powders, dusts, pastes, soluble powders, granules,suspo-emulsion concentrates, natural and synthetic materials impregnatedwith active compound, and microencapsulations in polymeric materials.

These formulations are produced in a known manner, for example by mixingthe active compounds with extenders, that is, liquid solvents and/orsolid carriers, optionally with the use of surfactants, that is,emulsifiers and/or dispersants and/or foam formers.

If the extender used is water, it is also possible to employ, forexample, organic solvents as cosolvents. The following are essentiallysuitable as liquid solvents: aromatics such as xylene, toluene, oralkylnaphthalenes, chlorinated aromatics and chlorinated aliphatichydrocarbons such as chlorobenzenes, chloroethylenes or methylenechloride, aliphatic hydrocarbons such as cyclohexane or paraffins, forexample mineral oil fractions, mineral and vegetable oils, alcohols suchas butanol or glycol and their ethers and esters, ketones such asacetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone,strongly polar solvents such as dimethylformamide and dimethylsulphoxide, or else water.

Solid carriers which are suitable are:

-   -   for example ammonium salts and ground natural minerals such as        kaolins, clays, talc, chalk, quartz, attapulgite,        montmorillonite or diatomaceous earth, and ground synthetic        materials such as highly-dispersed silica, alumina and        silicates; suitable solid carriers for granules are for example        crushed and fractionated natural rocks such as calcite, marble,        pumice, sepiolite and dolomite, or else synthetic granules of        inorganic and organic meals, and granules of organic material        such as sawdust, coconut shells, corn cobs and tobacco stalks;        suitable emulsifiers and/or foam formers are for example        nonionic and anionic emulsifiers such as polyoxyethylene fatty        acid esters, polyoxyethylene fatty alcohol ethers, for example        alkylaryl polyglycol ethers, alkylsulphonates, alkyl sulphates,        arylsulphonates, or else protein hydrolyzates; suitable        dispersants are for example ligninosulphite waste liquors and        methylcellulose.

Tackifiers such as carboxymethylcellulose and natural and syntheticpolymers in the form of powders, granules or latices, such as gumarabic, polyvinyl alcohol and polyvinyl acetate, or else naturalphospholipids such as cephalins and lecithins and syntheticphospholipids can be used in the formulations. Other possible additivesare mineral and vegetable oils.

It is possible to use colorants such as inorganic pigments, for exampleiron oxide, titanium oxide and Prussian Blue, and organic dyestuffs,such as alizarin dyestuffs, azo dyestuffs and metal phthalocyaninedyestuffs, and trace nutrients such as salts of iron, manganese, boron,copper, cobalt, molybdenum and zinc.

The formulations generally comprise between 0.1 and 95 percent by weightof active compounds, preferably between 0.5 and 90%.

The active compound combinations according to the invention aregenerally applied in the form of ready mixes. However, the activecompounds contained in the active compound combinations may also beapplied in the form of individual formulations which are mixed upon use,that is, in the form of tank mixes.

The novel active compound combinations, as such or in theirformulations, may furthermore also be used as a mixture with other knownherbicides, again with ready mixes or tank mixes being possible. Amixture with other known active compounds such as fungicides,insecticides, acaricides, nematicides, bird repellents, growthsubstances, plant nutrients and soil conditioners is also possible. Itmay furthermore be advantageous for specific applications, in particularfor the post-emergence method, to incorporate into the formulationsplant-compatible mineral or vegetable oils (for example the commercialproduct “Rako Binol”) or ammonium salts such as, for example, ammoniumsulphate or ammonium thiocyanate, as further additives.

The novel active compound combinations can be used as such, in the formof their formulations or the use forms which can be prepared from theseformulations by further dilution, such as ready-to-use solutions,suspensions, emulsions, powders, pastes and granules. Application iseffected in the customary manner, for example by pouring, spraying,atomizing, dusting or broadcasting.

The active compound combinations according to the invention can beapplied before and after emergence of the plants, that is to say by thepre- and post-emergence method. They may also be incorporated into thesoil prior to sowing.

The good herbicidal activity of the novel active compound combinationsis demonstrated by the examples below. Whereas there are deficits in theherbicidal action of the individual active compounds, the combinationsall have very good action against weeds which exceeds a simple additionof activities.

A synergistic effect in herbicides is always present when the herbicidalaction of the active compound combination exceeds the action of theactive compounds when applied individually.

The expected action for a given combination of two herbicides can becalculated as follows (cf. COLBY, S.R.: “Calculating synergistic andantagonistic responses of herbicide combinations”, Weeds 15, pages20-22, 1967):

If

-   -   X=% damage by herbicide A (active compound of the formula I) at        an application rate of p kg/ha    -   and    -   Y=% damage by herbicide B (active compound of the formula II) at        an application rate of q kg/ha    -   and    -   E=the expected damage of herbicides A and B at an application        rate of p and q kg/ha,    -   then        E=X+Y−(X*Y/100).

If the actual damage exceeds the calculated value, the combination has asuperadditive effect, that is to say a synergistic effect.

The expected activity for a given combination of three herbicides canlikewise be found in the literature cited above.

USE EXAMPLES

The required amount of active compound—or formulation—is dissolved in 2to 3 ml of the solvent (acetone or N,N-dimethylformamide), an emulsifier(1 ml) is added, if required, and the solution is diluted with water tothe desired concentration.

Mixtures are prepared by mixing a predetermined dissolved amount of thefirst active compound with the required amount of the second activecompound—and, if appropriate, with additional active compounds or otheringredients—and the mixture is then diluted with water to the desiredconcentration.

In the case of post-emergence tests, a surfactant (for example Renex 36)is usually added in a concentration of 0.1% to the spray solution.

The amount of active compound is chosen such that the desiredapplication rate per hectare (ha) is achieved.

Example A

Post-emergence test (greenhouse)

Test plants are grown under controlled conditions (temperature andlight). Once the plants have reached a height of 5 to 15 cm, the testcompound or combination of test compounds is sprayed such that theparticular amounts of active compound desired are applied per unit area.The concentration of the spray liquor is chosen such that the particularamounts of active compound are applied in 500 litres of water perhectare.

Following the spray application, the plant containers are placed in agreenhouse under constant conditions with respect to light andtemperature.

After about three weeks, the degree of damage to the plants is rated in% damage in comparison to the development of the untreated control.

The figures denote:

-   -   0%=no effect (like untreated control)    -   100%=total destruction

Active compounds, application rates, test plants and results are shownin the tables below, the terms used in the tables having the followingmeanings:

-   -   a.i.=active ingredient (active compound)    -   ha=hectare

In the table, metribuzin is a 70 WG formulation of the correspondingactive compound (“Sencor 70 WG”).

In the table, sulcotrione is a 300 SC formulation of the correspondingactive compound (“Mikado 300 SC”). TABLE A1 Active ChenopodiumChenopodium compound Application rate album album (formulation) (g ofai/ha) observed calculated* metribuzin 10 0 sulcotrione 20 90metribuzin + 10 + 20 100 90 sulcotrione

TABLE A2 Active Polygonum Polygonum compound Application rateconvolvolus convolvolus (formulation) (g of ai/ha) observed calculated*metribuzin 40 0 20 0 sulcotrione 80 60 40 30 20 0 metribuzin +sulcotrione 40 + 80 100 60 40 + 40 90 30 40 + 20 60 0 20 + 80 100 6020 + 40 80 30 20 + 20 60 0

TABLE A3 Active Amaranthus Amaranthus compound Application rateretroflexus retroflexus (formulation) (g of ai/ha) observed calculated*metribuzin 20 90 10 80 sulcotrione 80 60 40 20 metribuzin + sulcotrione20 + 80 100 96 20 + 40 100 92 10 + 80 100 92 10 + 40 100 84(500 ml/ha of Marlipal were added as additive)

TABLE A4 Active Polygonum Polygonum compound Application convolvolusconvolvolus (formulation) rate(g of ai/ha) observed calculated*metribuzin 40 0 20 0 sulcotrione 80 70 40 20 metribuzin + sulcotrione40 + 80 100 70 40 + 40 70 20 20 + 80 95 70 20 + 40 70 20(500 ml/ha of Marlipal were added as additive)

TABLE A5 Active Application Echinochloacrus Echinochloacrus compoundrate galli galli (formulation) (g of ai/ha) observed calculated*metribuzin 40 10 20 0 10 0 sulcotrione 80 80 40 40 20 20 metribuzin +40 + 80 100 82 sulcotrione 40 + 40 100 46 40 + 20 95 28 20 + 80 100 8020 + 40 90 40 20 + 20 60 20 10 + 80 95 80(500 ml/ha of Marlipal were added as additive)*The calculated values were determined using Colby's formula.

1. Herbicidal compositions, characterized in that they comprise aneffective amount of an active compound combination comprising (a) atleast one compound of the general formula (I)

in which R¹ represents straight-chain or branched alkyl having 1 to 6carbon atoms or represents phenyl and R² represents in each casestraight-chain or branched alkyl or alkylthio having in each case 1 to 6carbon atoms (“compounds of group 1”) and (b) at least one substitutedbenzoylcyclohexanedione of the general formula (II)

in which R³ represents nitro, cyano, halogen, or represents in each casehalogen-substituted, in each case straight-chain or branched alkyl,alkoxy, alkylthio, alkylsulphinyl or alkylsulphonyl having in each case1 to 6 carbon atoms, and R⁴ represents nitro, cyano, halogen, representsin each case optionally halogen-, C₁-C₄-alkoxy-, C₁-C₄-alkylthio-,C₁-C₄-alkylsulphinyl- or C₁-C₄-alkylsulphonyl-substituted, in each casestraight-chain or branched alkyl, alkoxy, alkylthio, alkylsulphinyl oralkylsulphonyl having in each case 1 to 6 carbon atoms, or representsalkylamino, dialkylamino, dialkylaminocarbonyl or dialkylaminosulphonylhaving in each case 1 to 6 carbon atoms in the alkyl groups which are ineach case straight-chain or branched (“active compounds of group 2”) andalso, if appropriate, additionally (c) a compound which improves cropplant compatibility, from the following group of compounds:4-dichloroacetyl-1-oxa-4-azaspiro[4.5]decane (AD-67),1-dichloroacetylhexa-hydro-3,3,8a-trimethylpyrrolo[1,2-a]pyrimidin-6(2H)-one(BAS-145138), 4-dichloroacetyl-3,4-dihydro-3-methyl-2H-1,4-benzoxazine(benoxacor), 1-methylhexyl 5-chloroquinoxalin-8-oxyacetate(cloquintocet-mexyl), α-(cyanomethoximino)phenylacetonitrile(cyometrinil), 2,4-dichlorophen-oxyacetic acid (2,4-D),2,2-dichloro-N-(2-oxo-2-(2-propenylamino)ethyl)-N-(2-propenyl)acetamide(DKA-24), 2,2-dichloro-N,N-di-2-propenylacetamide (dichlormid),N-(4-methylphenyl)-N′-(1-methyl-1-phenylethyl)urea (daimuron, dymron),4,6-dichloro-2-phenylpyrimidine (fenclorim), ethyl1-(2,4-dichlorophenyl)-5-trichloromethyl-1H-1,2,4-triazole-3-carboxylate(fenchlorazol-ethyl), phenylmethyl2-chloro-4-trifluoromethylthiazole-5-carboxylate (flurazole),4-chloro-N-(1,3-dioxolan-2-ylmethoxy)-α-trifluoroacetoxyphenoxime(fluxofenim), 3-dichloroacetyl-5-(2-furanyl)-2,2-dimethyloxazolidine(furilazole, MON-13900), ethyl4,5-dihydro-5,5-di-phenyl-3-isoxazolecarboxylate (isoxadifen-ethyl),(4-chloro-2-methylphen-oxy)acetic acid (MCPA),(±)-2-(4-chloro-2-methylphenoxy)propanoic acid (mecoprop), diethyl1-(2,4-dichlorophenyl)-4,5-dihydro-5-methyl-1H-pyrazole-3,5-dicarboxylate(mefenpyr-diethyl), 2-dichloromethyl-2-methyl-1,3-dioxolane (MG-191),1,8-naphthalic anhydride,Q-(1,3-dioxolan-2-ylmethoximino)phenylacetonitrile (oxabetrinil),2,2-dichloro-N-(1,3-dioxolan-2-ylmethyl)-N-(2-propenyl)acetamide(PPG-1292), 3-dichloro-acetyl-2,2,5-trimethyloxazolidine (R-29148),N-cyclopropyl-4-[[(2-methoxy-5-methylbenzoyl)amino]sulphonyl]benzamide,N-[[(4-methoxyacetyl-amino)phenyl]sulphonyl]-2-methoxybenzamide andN-[[(4-methylamino-carbonylamino)phenyl]sulphonyl]-2-methoxybenzamide(the latter are in each case known from WO-A-99/66795) (“activecompounds of group 3”).
 2. Herbicidal compositions according to claim 1,characterized in that they comprise, as active compound of group 1, acompound of the general formula (I), in which R¹ representsstraight-chain or branched alkyl having 1 to 5 carbon atoms orrepresents phenyl and R² represents in each case straight-chain orbranched alkyl or alkylthio having in each case 1 to 5 carbon atoms. 3.Herbicidal compositions according to claim 1 or 2, characterized in thatthey comprise, as active compound of group 1, a compound of the generalformula (I) in which R¹ represents methyl, ethyl, n- or i-propyl, n-,i-, s- or t-butyl, or rerpesents phenyl and R² represents methyl, ethyl,n- or i-propyl, n-, i-, s- or t-butyl, methylthio, ethylthio, n- ori-propylthio, n-, i-, s- or t-butylthio.
 4. Herbicidal compositionsaccording to claims 1 to 3, characterized in that they comprise, asactive compound of group 1, a compound of the general formula (I) inwhich R¹ represents n- or i-propyl, n-, i-, s- or t-butyl, or representsphenyl and R² represents methyl, ethyl, n- or i-propyl, methylthio,ethylthio, n- or i-propylthio.
 5. Herbicidal compositions according toclaims 1 to 4, in which the active compound of group 1 is metribuzin,metamitron or ethiozin.
 6. Herbicidal compositions according to claims 1to 5, characterized in that they comprise, as active compound of group2, a compound of the general formula (II) in Which R³ represents nitro,cyano, halogen, or represents in each case optionallyhalogen-substituted, in each case straight-chain or branched alkyl,alkoxy, alkylthio, alkylsulphinyl or alkylsulphonyl having in each case1 to 5 carbon atoms and R⁴ represents nitro, cyano, halogen, representsin each case optionally halogen-, C₁-C₄-alkoxy-, C₁-C₄-alkylthio-,C₁-C₄-alkylsulphinyl- or C₁-C₄-alkylsulphonyl-substituted, in each casestraight-chain or branched alkyl, alkoxy, alkylthio, alkylsulphinyl oralkylsulphonyl having in each case 1 to 5 carbon atoms, or representsalkylamino, dialkylamino, dialkylaminocarbonyl or dialkylaminosulphonylhaving in each case 1 to 5 carbon atoms in the alkyl groups, which arein each case straight-chain or branched.
 7. Herbicidal compositionsaccording to claims 1 to 6, characterized in that they comprise, asactive compound of group 2, a compound of the general formula (II) inwhich R³ represents nitro, cyano, fluorine, chlorine, bromine, iodine,or represents in each case optionally fluorine- and/orchlorine-substituted methyl, ethyl, n- or i-propyl, n-, i-, s- ort-butyl, methoxy, ethoxy, n- or i-propoxy, methylthio, ethylthio, n- ori-propylthio, methylsulphinyl, ethylsulphinyl, n- or i-propylsulphinyl,methylsulphonyl or ethyl-sulphonyl and R⁴ represents nitro, cyano,fluorine, chlorine, bromine, iodine, represents in each case optionallyfluorine-, chlorine-, methoxy-, ethoxy-, n- or i-propoxy-, methylthio-,ethylthio-, n- or i-propylthio-, methyl-sulphinyl-, ethylsulphinyl-, n-or i-propylsulphinyl-, methylsulphonyl- or ethylsulphonyl-substitutedmethyl-, ethyl-, n- or i-propyl, n-, i-, s- or t-butyl, methoxy, ethoxy,n- or i-propoxy, methylthio, ethylthio, n- or i-propylthio,methylsulphinyl, ethylsulphinyl, n- or i-propyl-sulphinyl,methylsulphonyl or ethylsulphonyl, or represents methyl-amino,ethylamino, n- or i-propylamino, dimethylamino, diethyl-amino,dipropylamino, dimethylaminocarbonyl, diethylaminocarbonyl,dimethylaminosulphonyl or diethylaminosulphonyl.
 8. Herbicidalcompositions according to claims 1 to 7, characterized in that theycomprise, as active compound of group 2, a compound of the generalformula (II) in which R³ represents nitro, cyano, fluorine, chlorine,bromine, or represents in each case optionally fluorine- and/orchlorine-substituted methyl, ethyl, methoxy, ethoxy, methylthio,ethylthio, methylsulphinyl, ethyl-sulphinyl, methylsulphonyl orethylsulphonyl and R⁴ represents nitro, cyano, fluorine, chlorine,bromine, or represents in each case optionally fluorine-, chlorine-,methoxy-, ethoxy-, methylthio-, ethylthio-, methylsulphinyl-,ethylsulphinyl-, methylsulphonyl-, or ethylsulphonyl-substituted methyl,ethyl, methoxy, ethoxy, methylthio, ethylthio, methylsulphinyl,ethylsulphinyl, methylsulphonyl or ethylsulphonyl.
 9. Herbicidalcomposition according to claims 1 to 8 in which the active compound ofgroup 2 is sulcotrione or mesotrione.
 10. Herbicidal compositions,comprising metribuzin and sulcotrione.
 11. Herbicidal compositionsaccording to claims 1 to 10, which comprise, as active compound of group3, cloquintocet-mexyl, isoxadifen-ethyl, mefenpyr-diethyl, AD-67,BAS-145138, benoxacon, dichlormid or furilazole (MON-13900).
 12. Use ofa composition according to any of claims 1 to 11 for controllingunwanted plants.
 13. Method for controlling unwanted plants,characterized in that compositions according to any one of claims 1 to11 are allowed to act on the unwanted plants and/or their habitat. 14.Process for preparing a herbicidal composition, characterized in that acomposition according to any one of claims 1 to 11 is mixed withsurfactants and/or extenders.
 15. Compositions according to any ofclaims 1 to 11, characterized in that from 0.01 to 100 parts by weightof active compound of group II are present per part by weight of activecompound of group I.